HR202 Humidity Module

Description

Humidity Module with 1 Channel Relay and LED Indicator LM393 Humidity Sensor HR202 Digital Output Module

Tutorial: How to Use Humidity Module with Relay and LED

The HR202 humidity module is a useful component for projects requiring automatic humidity management. It is ideal for smart gardening enthusiasts or anyone who wants to monitor the environment.

What you need

• Arduino Uno
• Jumper Wires (various colors)
• 5V Power Supply

Steps

1. Connect the VCC and GND pins of the HR202 module to the Arduino power supply.
2. Connect the DOUT pin to the digital input pin of the Arduino.
3. If necessary, connect the relay to an external device (check the datasheet for the correct voltage).
4. Connect the LED pins to the power supply and the HR202 module as a visual indicator.
5. Write the Arduino sketch to read humidity from the sensor.
6. Test the connection with a simple loop that turns the relay on/off based on humidity values.
7. If everything works, customize the humidity threshold to activate the relay automatically.
8. Test the project on a small external device like a water pump.

Example code

const int sensorPin = 2; // Pin digitale dove è collegato DOUT del sensore
const int relayPin = 7; // Pin di controllo del relè
void setup() {
  pinMode(sensorPin, INPUT);
  pinMode(relayPin, OUTPUT);
}
void loop() {
  if (digitalRead(sensorPin) == HIGH) {
    digitalWrite(relayPin, HIGH); // Attiva il relè se DOUT è alto
  } else {
    digitalWrite(relayPin, LOW); // Disattiva il relè altrimenti
  }
}

Mini project

Create an automatic irrigation system for a plant. Connect the water pump to the HR202 relay module and set the desired humidity level.

Common mistakes

• Connect the DOUT pin to an analog pin on the Arduino.
• Do not check the correct voltage for the relay before connecting it.
• Forget to add a current-limiting resistor for the LED.
• Use an incorrect humidity threshold in the code.

Recommended accessories

• Arduino Uno
• Jumper Connections (various colors)
• 5V Relay
• Water Pump

Frequently asked questions

Does the relay only activate when the humidity is too high?
No, you can set the humidity threshold in the code.

Can I connect multiple HR202 sensors to a single Arduino board?
Yes, but you need to add pull-up resistors and modify the code to handle different pins.

What is the difference between this module and one without a relay?
This module includes an integrated relay that can automatically control external devices based on humidity.